Evidence that a respiratory shield in Escherichia coli protects a low-molecular-mass Fe^II pool from O₂-dependent oxidation.

ABSTRACT: Iron is critical for virtually all organisms, yet major questions remain regarding the systems-level understanding of iron in whole cells. Here, we obtained Mössbauer and EPR spectra of Escherichia coli cells prepared under different nutrient iron concentrations, carbon sources, growth phases, and O₂ concentrations to better understand their global iron content. We investigated WT cells and those lacking Fur, FtnA, Bfr, and Dps proteins. The coarse-grain iron content of exponentially growing cells consisted of iron-sulfur clusters, variable amounts of nonheme high-spin Fe^II species, and an unassigned residual quadrupole doublet. The iron in stationary-phase cells was dominated by magnetically ordered Fe^III ions due to oxyhydroxide nanoparticles. Anal

SUBMITTER: Wofford JD 

PROVIDER: S-EPMC6322884 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature